A soft-spoken mother becomes an agitated campaigner when talking about Chinese children buried under loads of schoolwork.

Hu Lanlan has written to the Ministry of Education, appealing for changes she believes will be crucial for saving China's more than 200 million children.

Hu, whose teenage twins attend junior high school in Beijing, was prompted to write the letter after a series of suicides over poor grades or heavy loads of schoolwork, she said.

Ten years ago, a friend's 14-year-old son hanged himself because he had not finished his mountain of schoolwork and feared punishment.

"Similar tragedies, however, are still happening today," she wrote in the letter. "Each year, dozens of children commit suicide under the pressure of too much homework and their parents' expectations for them to enter top schools."

The youngest of these children was just nine years old.

Last Tuesday, a 12-year-old boy in Guangzhou, capital of south China's Guangdong Province, jumped from a 16th-floor window, leaving behind an English exercise book in which he wrote: "I'm going to die. Bye."

The boy had poor grades and sometimes failed to finish his homework. The day before he died, his teacher had torn his Chinese textbook in pieces because the boy had not done his assignment properly.

"As an ordinary citizen, I make my appeal for those millions of Chinese children devastated by the exam-based education, out of my love for the kids and the determination to do something for their physical and mental health," Hu wrote.

Growing academic pressure is a threat to children's psychological health, according to Dr Ye Yiduo, a child psychologist in eastern Fujian Province.

In a survey of 6,091 children, he found that at least 20 percent of primary school students, 44 percent of junior high students and 52 percent of senior high students had psychological problems.

"These are not just abstract figures," said Hu, who quoted the figures in her letter. "Behind these figures, so many children and families are suffering. Pre-teens get up drowsily at daybreak to go to school and stay up late to finish their assignments. Many attend training courses on weekends and holidays in order to excel."

When Hu was young, in the 1980s, she said she had more fun than homework.

"Today, however, children are like machines running around the clock. In an ailing education system, teachers exert too much pressure on children because they themselves feel the stress from school authorities," she said. "We should understand the children, who are not as mentally strong as we might think, and create a healthier environment to boost their confidence and enable them to truly love school life."

Hu called for laws ensuring children can get at least eight hours of sleep each night and exempting primary school students from homework.

She also demanded an end to the exam-based evaluation system by canceling tests and rankings during primary school and junior high years.

An education ministry official said yesterday they were "attentive to this letter" and were "checking the situation," but refused to comment further.